Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
03-07-2008, 06:46 AM   #1
Site Supporter
amateur6's Avatar

Join Date: Mar 2007
Location: Rhode Island
Photos: Gallery
Posts: 175
What difference does "D-Range 200%" really make?

So, I certainly haven't had time to make a comparison -- anyone else? Or is there anything already out there? Best time to use it/when never to use it?

Just wondering.

03-07-2008, 08:58 AM   #2
Forum Member




Join Date: Jan 2008
Location: Corvallis Oregon
Posts: 70
I havent made the time to try it. But, I'm guessing that if it really was worth it, it would be on by default.


Pete
03-07-2008, 10:53 AM   #3
Forum Member




Join Date: Jan 2008
Location: Idaho, USA
Posts: 60
QuoteOriginally posted by petez Quote
I havent made the time to try it. But, I'm guessing that if it really was worth it, it would be on by default.

Pete
You may be right about it not being worth it, but I think one reason it is not on by default is that it increases the ISO to at least 200. They wouldn't want the base ISO to be 200 by default. Others have described how it actually works, but I like to think of it as exposing the highlights at ISO 100 and the rest of the photo at ISO 200. Obviously not that simple but I think that in situations where you are going to have trouble holding detail in the highlights that EDR is going to turn out to be quite useful.
Mike
03-07-2008, 10:58 AM   #4
Inactive Account




Join Date: Oct 2006
Location: Boise, Idaho
Photos: Gallery | Albums
Posts: 1,414
Pentax has admitted that it increases shadow noise. I'm not interested.

03-07-2008, 11:07 AM   #5
Veteran Member
WMBP's Avatar

Join Date: Dec 2006
Location: Dallas, Texas
Photos: Gallery
Posts: 2,496
I've also been scratching myself about this. I have taken a few test photos with it on and with it off but I can't say that I yet understand the difference--or the point. Perfect example of where the owner's manual is pretty unhelpful. Tells you HOW to turn it on, but doesn't say much about why you would want to or what difference it will really make.

Will
03-07-2008, 11:20 AM   #6
Site Supporter
dave kitson's Avatar

Join Date: Sep 2006
Location: Lichfield, UK
Photos: Gallery | Albums
Posts: 460
QuoteOriginally posted by WMBP Quote
I've also been scratching myself about this. I have taken a few test photos with it on and with it off but I can't say that I yet understand the difference--or the point. Perfect example of where the owner's manual is pretty unhelpful. Tells you HOW to turn it on, but doesn't say much about why you would want to or what difference it will really make.

Will

I've played with it a bit. I think that in this mode the K20 amplifies the highlights less (and possibly amplifies the shadow tones more).

It does help avoid blown highlights, but makes for rather noisier shadows.

dave
03-07-2008, 11:36 AM   #7
Veteran Member
WMBP's Avatar

Join Date: Dec 2006
Location: Dallas, Texas
Photos: Gallery
Posts: 2,496
QuoteOriginally posted by WMBP Quote
I've also been scratching myself....
Um, I think I meant to say "scratching my head." Just want to make that clear.

Will
03-07-2008, 12:05 PM   #8
Inactive Account




Join Date: Mar 2007
Location: James City County, Virginia
Photos: Gallery
Posts: 322
QuoteOriginally posted by WMBP Quote
Um, I think I meant to say "scratching my head." Just want to make that clear.

Will
Only an english professor would have picked up on that.

03-07-2008, 12:46 PM   #9
Veteran Member
WMBP's Avatar

Join Date: Dec 2006
Location: Dallas, Texas
Photos: Gallery
Posts: 2,496
QuoteOriginally posted by squarerigger Quote
Only an english professor would have picked up on that.
Well, I was a Latin professor, but, hey, correct English is very nearly as dead a language as Latin, so there's little difference. ;-)

Will
03-07-2008, 12:53 PM   #10
Site Supporter
amateur6's Avatar

Join Date: Mar 2007
Location: Rhode Island
Photos: Gallery
Posts: 175
Original Poster
QuoteOriginally posted by WMBP Quote
Um, I think I meant to say "scratching my head." Just want to make that clear.


Thanks all -- but especially Will.
03-07-2008, 02:09 PM   #11
Veteran Member
roentarre's Avatar

Join Date: Oct 2006
Location: Melbourne, Australia
Posts: 11,794
QuoteOriginally posted by davemdsn Quote
Pentax has admitted that it increases shadow noise. I'm not interested.
Maybe that is why I am not so impressed with shadow noise in many of the shots above ISO 800...
03-07-2008, 02:22 PM   #12
Veteran Member
Matjazz's Avatar

Join Date: Sep 2006
Location: EU/Slovenia
Photos: Gallery
Posts: 774
Does EDR work for RAW as well?
03-07-2008, 02:25 PM   #13
Site Supporter
dave kitson's Avatar

Join Date: Sep 2006
Location: Lichfield, UK
Photos: Gallery | Albums
Posts: 460
QuoteOriginally posted by Matjazz Quote
Does EDR work for RAW as well?
Yes, you can generate RAW images with 'd-range 200%' enabled

dave
03-07-2008, 03:06 PM   #14
Pentaxian
falconeye's Avatar

Join Date: Jan 2008
Location: Munich, Alps, Germany
Photos: Gallery
Posts: 6,862
QuoteOriginally posted by dave kitson Quote
I've played with it a bit. I think that in this mode the K20 amplifies the highlights less (and possibly amplifies the shadow tones more).

It does help avoid blown highlights, but makes for rather noisier shadows.
I've no clue what this EDR may be. If the above is true, however, the explaination may be as simple as this:
The K20D just underexposes by 1 stop w/o showing so in the histogram, i.e., it pretends to use one ISO step more than it actually does. This would be in line with ISO100 not being available anymore. It can then apply tone mapping keeping the highlights and boosting the shadows 1 step when rendering JPEGs. However, this way it would render more noise into the shadows.

This theory is consistent with everything I have heard about it so far. And if true, it isn't for people shooting RAW and controlling histograms.

And most of all, it would have to be switched off in normal light conditions, not be ON by default.

Everything would have to be in the manual.

The problem with manuals is this: They are outsourced to "document writer" companies and will contain at most as much information as we find out by ourselves playing with it for 2 days. Because this is exactly like those companies are working. Brave new world!
03-07-2008, 07:21 PM   #15
DAZ
Veteran Member
DAZ's Avatar

Join Date: Sep 2006
Location: Everett, WA USA
Photos: Gallery
Posts: 699
The sun came out for a day so I was able to get out and play with my K20D. I tried it out on some birds by a nearby lake. Taking photos of the birds I was blowing the highlights. This is normal as I have to usually expose more to the left then I like and when I did that I did not clip the highs as much. When I used the D-range 200% I could expose normal and had even less blown highlights then even the way I expose to the left.

I don’t’ know how the camera is doing this but I can think of 2 ways the camera could do this. One is to just under expose like I normally do use a curve PP to even it all out as has been suggested. I don’t think this is what the camera is doing. First this would not be a 200% increase and Pentax calling it that would be setting themselves up to be sued if the did not have a lot of lawyer talk in the fine print. I don’t see and of that fine print. Second if that was what they did they could do that without limiting it to ISO 200 and up.

The second way is like a compressor/limiter that is used in audio. What you do to not clip in audio is first you amplify your signal then you increase the attenuation at the high end to limit the signal and not clip. This makes the system non-linear and this lets the system handle a bigger range. Now as there are more A/D steps at the high end then at low end (more at the high end then can normally be used) this would be a good way to use what is normally wasted. This could be why you can’t us this with 100 ISO.

Now a system like the second works best when you start with a strong signal. As it will add noise to a noisier to signal like at higher ISOs so it maybe better to not use it especially if you not need it. This maybe why it is not on by default. At 200 ISO in strong sun for example you may not see the noise differents at all.

If this is the way it works you will only see the extra range if you are going to clip. If you expose so you don’t clip then turn on 200% you probably will not see anything. If you expose for like -1 stop over then you get that back and if you are at 200 ISO in good light you should see very little noise in the shadows.

DAZ

Last edited by DAZ; 03-08-2008 at 06:08 AM.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
camera, dslr, photography, time
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
moderator - pls make a thread about "new K-x has something loose/noise/etc." sticky? yuwlyuwl Troubleshooting and Beginner Help 7 03-09-2010 04:44 AM
ebay "make an offer" - any advice jfsavage General Talk 10 12-10-2008 06:17 PM
K20D "D" Range vs 100 iso benjikan Pentax DSLR Discussion 14 03-22-2008 07:51 PM
What is difference "APO" and "ED" glass in a lens? kathyk Pentax SLR Lens Discussion 4 03-06-2008 08:59 AM
Difference between a macro and "regular lens" weatherwise2 Pentax SLR Lens Discussion 3 01-01-2008 04:40 AM



All times are GMT -7. The time now is 09:50 PM. | See also: NikonForums.com, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top